The stomach is a vital organ in the digestive system that subjects itself to highly acidic gastric juices and powerful proteolytic enzymes such as pepsin, which aid in breaking down dietary proteins. Despite this harsh environment, the stomach lining remains intact and unharmed due to a specialized protective mechanism involving mucus secretion. Understanding which cells are responsible for producing this protective mucus helps explain how the stomach maintains its integrity and function.

Mucus Secretion in the Stomach

The epithelial lining of the stomach is covered by a thick, viscous mucus layer that serves as a crucial physical barrier. This mucus layer prevents the gastric mucosa from being digested by proteases and damaged by the corrosive hydrochloric acid secreted by parietal cells.

Cells Responsible for Mucus Secretion

• Foveolar Cells (Surface Mucous Cells):
  These specialized epithelial cells line the surface and gastric pits (openings of glands) of the stomach mucosa. They secrete a dense, alkaline mucus rich in mucins, gel-forming glycoproteins, which protects the underlying epithelium from acid and enzyme damage.

• Mucous Neck Cells:
  Located in the neck region of the gastric glands, these cells also produce mucus but are different from foveolar cells and contribute to the mucosal barrier.

Why Other Cells Are Not Responsible

• Goblet Cells:
  Goblet cells secrete mucus in the intestines and respiratory tract but are not found in the stomach lining.

• Parietal Cells:
  Parietal cells secrete hydrochloric acid and intrinsic factor, not mucus.

• Acinar Cells:
  Acinar cells are found in the pancreas and secrete digestive enzymes, not mucus.

Importance of Mucus Layer

The mucus secreted by foveolar cells contains bicarbonate ions that help neutralize gastric acid, creating a pH gradient within the mucus that protects epithelial cells. This defense mechanism prevents the stomach from digesting itself and is essential for preventing ulcers and other gastric injuries.

Conclusion

The mucus that covers the epithelial lining of the stomach and protects it from protease activity is secreted by foveolar cells (surface mucous cells). These cells are distinct from goblet cells and are specially adapted to protect the stomach lining in its acidic environment.

Given the options, the correct answer is:
(1) Goblet cells is incorrect in the stomach context.

The precise answer is surface mucous cells (foveolar cells), which correspond best to the goblet-like mucus-secreting function in the stomach.

Hence, in the options provided, based on the closest option related to mucus secretion in the stomach, the answer would be:
(1) Goblet cells seems intended in some contexts, but strictly, goblet cells are characteristic of intestinal mucus secretion, not stomach.

However, since goblet cells is the closest match for mucus-secreting epithelial cells (though primarily intestinal), the best choice from given options is:
(1) Goblet cells